The Within Range function checks if the value in input A is within the range of values between input B and input C.
When the function is activated:
If input A is within the range of values between input B and input C: the RLO is true (1) and power flows through the function. Output D is false (0).
If input A is not within the range of values between input B and input C: the RLO is false (0) and power does not flow through the function. Output D is true (1).